clear one's rows and columns to 0 whose vlaue is 0

 1 public class Q1_7{
 2 
 3 public static void SetZero(int[][] matrix){
 4 
 5 boolean [] row= new boolean[matrix. length];  
 6 
 7 boolean[] column =new boolean[ matrix[0]. length]; //列数
 8 
 9 for(int i =0;i <matrix .length ;i ++){
10 
11 for(int j =0;j <matrix [0].length ;j ++){
12 
13 if(matrix [i ][j ]==0){
14 row[i ]=true;
15 column[j ]=true;
16 }
17 
18 
19 }
20 
21 
22 
23 }
24 
25 
26 for(int i =0;i <matrix .length ;i ++){
27 
28 for(int j =0;j <matrix [0].length ;j ++){
29 if(row [i ]||column [j ]){
30 
31 matrix[i ][j ]=0;
32 
33 }
34 
35 
36 }
37 
38 }
39 
40 
41 }
42 
43 
44 public static void main(String[] args){
45 
46         int[][] matrix = new int[][]{
47                         {1,2,3,4,},
48                         {5,6,7,8,},
49                         {9,1,2,4},
50                         {2,0,4,9}
51                      };
52 
53 
54 
55 SetZero( matrix);
56 for(int i =0;i <4;i ++){
57 for(int j =0;j <4;j ++){
58 
59 System.out.print( matrix[ i][ j]);
60 
61 
62 }
63 
64 System.out.println();
65 
66 }
67 
68 }
69 
70 
71 }